Title: "Meaurements of the Proton Structure Functions F2 and FL from Radiative Events with Zues Detector at HERA"

Abstract:

The proton structure function F2 has been measured in e^+p collisions wiht hard photon radiation from the initial state positron in the kinematic range 0.3 < Q^2<40.0 GeV^2 and 8.10 < X < 1.8.10^-1 using an intergrated luminosity of 3.78 pd^-1 recorded in 1996 with ZEUS detector at HERA. These bridge the gap in the kinematic coverage between previous F_2 measurements from HERA and those from fixed target experiments. With the same type of events, using an intergrated luminosity of 34.33 pd^-1 logged in 1996 and 1997, the longitudinal structure function F_L is found to be 0.53 ^{0.21}_{0.20} (stat.)^{0.21}_{0.46} (sys.). This value is consistent with direct perturbative QCD calculations as well as with an indirect determination based on extrapolating the \gamma p cross section employing perturbative QCD.